Stats straight from the source

About the Riot Games API

With this site we hope to provide the League of Legends developer community with access to game data in a secure and reliable way. This is just part of our ongoing effort to respond to players' and developers' requests for data and to arm the community with more ways to contribute to the player experience. We want this API to meet the same high standards as our in-game experiences, so we'll be iterating and evolving as we hear your feedback and suggestions (so share 'em all).